JIRA AF-1205 adds a system property defining Workbench m2 repository URL.
This property should be defined also in Workbench scripts, it should point to Workbench URL. For more info see docs.

Otherwise...
10:04:02,829 ERROR [org.guvnor.m2repo.backend.server.M2RepoServiceImpl] (default task-60) The property org.appformer.m2repo.url is not correctly set. The workbench will use a direct file path to the m2 repository and this should only be used when test the workbench.